A square workpiece cutting system and cutting method based on laser height measurement

Abstract

The present invention relates to the field of chip cutting technology, and provides a square workpiece cutting system and a cutting method based on laser height measurement. By measuring the height of a specified position of a workpiece, the fitting surface information of the workpiece can be accurately restored, thereby compensating the height of cutting components at different positions, and the height of any position point is calculated by interpolation based on the fitting surface information, so that the height of some position points can be verified, thereby ensuring the cutting accuracy, and the cutting is adjusted in real time according to the surface height, ensuring the consistency of the cutting depth, and minimizing the generation of cutting waste, thereby saving costs, and after the verification meets the requirements, there is no need to continue the verification, thereby achieving subsequent direct cutting, which is beneficial to improving the cutting efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of chip cutting, and in particular to a square workpiece cutting system and a cutting method based on laser height measurement. Background Art

[0002] The dicing machine table is one of the important parts of the dicing machine. Its main function is to serve as a carrier for the wafer to be cut. The dicing machine cuts the wafer by using the dicing blade at a certain height above it. The distance between the dicing blade and the dicing machine table determines the final cutting depth.

[0003] For workpieces that do not need to be completely cut off (half-cut), the accuracy of the cutting table that carries the workpiece has a height difference of 0-50 microns. At the same time, the thickness of each area of ​​the workpiece itself will have a height difference of tens of microns. However, since the height of the cutting blade is fixed, the depth of cutting into the workpiece cannot be accurately controlled, which affects the final cutting accuracy. Summary of the invention

[0004] The purpose of the present invention is to provide a square workpiece cutting system and cutting method based on laser height measurement, so as to solve the problem that the existing workpiece that needs to be half-cut cannot ensure the cutting accuracy of the workpiece due to the fixed cutter head during cutting.

[0005] In a first aspect, an embodiment of the present invention provides a square workpiece cutting system based on laser height measurement, which is used to half-cut the square workpiece, comprising:

[0006] At least one set of cutting workbenches, the cutting workbenches are used to place square workpieces to be cut, the cutting workbenches are provided with a rectangular stage for adsorbing the square workpieces, and the cutting workbenches move in a feeding manner along the X-axis direction;

[0007] A cutting assembly, wherein the cutting assembly moves along the Y-axis direction to cut the square workpiece;

[0008] A laser distance measuring module, which is arranged above the cutting workbench and is used for laser height measurement of the square workpiece;

[0009] A control module, the control module is electrically connected to the laser ranging module, the cutting table and the cutting assembly, and is configured to obtain the height information of multiple sampling points on the surface of the square workpiece along the cutting direction collected by the laser ranging module, and obtain the workpiece fitting surface information by fitting the height information of the multiple sampling points; take verification points at several positions on the surface of the square workpiece, and perform interpolation calculation on the positions of the verification points according to the workpiece fitting surface information to obtain the fitting height information of the verification points; verify whether the difference between the fitting height information and the actual height information of the verification points is within the expected cutting depth fluctuation range, and determine whether to adjust the sampling points according to the verification results; wherein the sampling points are located on a straight line parallel or perpendicular to the cutting direction, and a straight line connecting any two adjacent sampling points parallel or perpendicular to the cutting direction is connected to obtain a set of straight lines as the workpiece fitting surface information, and the verification point is a point on a straight line connecting any two sampling points parallel or perpendicular to the cutting direction.

[0010] Optionally, performing interpolation calculation on the position of the verification point according to the workpiece fitting surface information to obtain fitting height information of the verification point includes:

[0011] A straight line formed by connecting any two adjacent sampling points parallel or perpendicular to the cutting direction is determined, and the height corresponding to the verification point on the straight line is used as the fitting height value, so as to obtain the fitting height information of the verification point.

[0012] Optionally, the heights of the multiple sampling points are obtained by fixed-point measurement, the multiple sampling points are arranged along the X-axis direction and equally divided along the Y-axis direction, and the verification point is located at the midpoint of two adjacent sampling points along the X-axis direction and the midpoint of two adjacent sampling points along the Y-axis direction.

[0013] Optionally, verifying whether the difference between the fitted height information and the actual height information of the verification point is within the expected cutting depth fluctuation range includes:

[0014] After all cutting is completed along the cutting path, the real height information corresponding to the N verification points is verified; if the difference between the fitting height information of the N verification points on the square workpiece and the corresponding real height information is all within the expected cutting depth fluctuation range, it indicates that the cutting accuracy of the square workpiece meets the requirements; if the difference between the fitting height information of the N verification points on the square workpiece and the corresponding real height information exceeds the expected cutting depth fluctuation range, the cutting is stopped and the number of sampling points is increased again and verified again N times until the N verifications meet the accuracy requirements;

[0015] If M consecutive square workpieces in a batch of incoming materials are verified, it means that the cutting accuracy of the batch of incoming materials meets the requirements and the subsequent square workpieces can be cut directly; wherein, the real height information of the verification point is obtained in advance through the laser ranging module or obtained through other measuring tools after cutting.

[0016] Optionally, verifying whether the difference between the fitted height information and the actual height information of the verification point is within the expected cutting depth fluctuation range includes:

[0017] The real height information of the verification point between two adjacent sampling points is verified for the first time. If the difference between the real height information and the fitting height information corresponding to the verification point is within the expected cutting depth fluctuation range, the verification is repeated N-1 times in the same way. If it is found that the difference between the real height information and the fitting height information corresponding to any verification point exceeds the expected cutting depth fluctuation range, the cutting is stopped and the number of sampling points is increased again and verified again N times until the N verifications meet the accuracy requirements. If M consecutive square workpieces in a batch of incoming materials are verified, it means that the cutting accuracy of the batch of incoming materials meets the requirements, and the subsequent square workpieces are directly cut. The real height information of the verification point is obtained in advance by the laser ranging module.

[0018] Optionally, verifying whether the difference between the fitted height information and the actual height information of the verification point is within the expected cutting depth fluctuation range includes:

[0019] The heights of the multiple sampling points are obtained by scanning and measuring with the laser ranging module, and the actual height information of the verification point is obtained by scanning at the same time, and the verification is performed by comparing the actual height information of the verification point with the fitting height information of the verification point;

[0020] If the difference between the actual height information of the verification point and the fitting height information at the corresponding position of the fitting surface information exceeds the expected cutting depth fluctuation range, it is necessary to redetermine the number of sampling points and the distance between two adjacent sampling points.

[0021] Optionally, the laser ranging module is connected to the cutting assembly via a connector and moves synchronously with the cutting assembly; or, the laser ranging module is connected to a Y-axis driving module installed on the top of the base.

[0022] Optionally, the square workpiece cutting system based on laser height measurement further includes: an image detection module, which is connected to a Y-axis driving module installed on the top of the base and is used for automatically aligning the square workpiece or checking the cutting condition.

[0023] Optionally, the cutting workbenches are divided into two groups, and the two groups of cutting workbenches are arranged side by side along the Y-axis direction and share the image detection module and the laser ranging module.

[0024] Optionally, the expected cutting depth of the square workpiece is between 100 microns and 150 microns, and the fluctuation range of the expected cutting depth is required to be between -15 microns and +15 microns.

[0025] In a second aspect, an embodiment of the present invention provides a square workpiece cutting method based on laser height measurement, based on the square workpiece cutting system based on laser height measurement as described in the first aspect, the square workpiece cutting method includes:

[0026] S100, obtaining the reference plane height of the cutting table;

[0027] S200, obtaining the heights of a plurality of sampling points on the surface of a square workpiece placed on the cutting workbench along a cutting direction;

[0028] S300, obtaining workpiece fitting surface information according to the height fitting of the plurality of sampling points;

[0029] S400, taking verification points at a plurality of positions on the surface of the square workpiece, and performing interpolation calculation on the positions of the verification points according to the workpiece fitting surface information to obtain fitting height information of the verification points;

[0030] S500, verifying whether the difference between the actual height information and the fitted height information of the verification point is within the expected cutting depth fluctuation range, and determining whether to adjust the sampling point according to the verification result.

[0031] The embodiments of the present invention have at least the following technical effects:

[0032] The square workpiece cutting system and cutting method based on laser height measurement provided by the embodiments of the present invention can accurately restore the fitting surface information of the workpiece by measuring the height of the specified position of the workpiece, thereby compensating the height of the cutting components at different positions, and interpolating and calculating the height of any position point based on the fitting surface information, so that the height of some position points can be verified to ensure the cutting accuracy, and the cutting is adjusted in real time according to the surface height to ensure the consistency of the cutting depth, and the generation of cutting waste can be minimized, thereby saving costs, and after the verification meets the requirements, there is no need to continue verification, thereby achieving subsequent direct cutting, which is beneficial to improving cutting efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 A schematic diagram of the overall structure of a square workpiece cutting system based on laser height measurement provided by an embodiment of the present invention;

[0035] Figure 2 A schematic diagram of the partial structure of a square workpiece cutting system based on laser height measurement provided by an embodiment of the present invention;

[0036] Figure 3 A schematic structural diagram of a cutting workbench of a square workpiece cutting system based on laser height measurement provided by an embodiment of the present invention;

[0037] Figure 4 A schematic diagram of coordinates of sampling points selected by a square workpiece cutting system based on laser height measurement provided by an embodiment of the present invention;

[0038] Figure 5 A schematic diagram of workpiece fitting surface information obtained by fitting sampling points on a square workpiece surface provided by an embodiment of the present invention;

[0039] Figure 6 The embodiment of the present invention provides Figure 5 Schematic diagram of workpiece fitting surface information after interpolation calculation;

[0040] Figure 7 A schematic diagram of a cutting route of verification points obtained by interpolation calculation of a square workpiece surface provided by an embodiment of the present invention;

[0041] Figure 8 A schematic diagram of a single rectangular unit in workpiece fitting surface information obtained by fitting sampling points of a square workpiece surface provided by an embodiment of the present invention;

[0042] Fig. 9 A schematic diagram of the connection of a control module of a square workpiece cutting system based on laser height measurement provided by an embodiment of the present invention;

[0043] Fig.10 A flow chart of a square workpiece cutting method based on laser height measurement provided in an embodiment of the present invention.

[0044] icon:

[0045] 100-cutting table; 110-reference plane; 200-cutting assembly; 300-laser distance measurement module; 400-image detection module; 500-square workpiece; 510-sampling point; 520-interpolation cutting line in the Y-axis direction; 530-interpolation cutting line in the X-axis direction; 600-control unit. DETAILED DESCRIPTION

[0046] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] Those skilled in the art will understand that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those generally understood by those skilled in the art in the field to which the present invention belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless specifically defined as here.

[0048] Those skilled in the art will appreciate that, unless otherwise stated, the singular forms "a", "an", "said" and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of the present invention refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof. The term "and / or" used herein includes all or any unit and all combinations of one or more associated listed items.

[0049] Combination Figures 1 to 9 As shown, an embodiment of the present invention provides a square workpiece cutting system based on laser height measurement, which is used to half-cut the square workpiece 500. Half-cutting means that the square workpiece 500 does not need to be completely cut through, but only needs to be cut into a certain depth. The square workpiece cutting system mainly includes: at least one set of cutting worktables 100, cutting components 200, laser ranging modules 300 and control units 600.

[0050] The cutting table 100 is used to place the square workpiece 500 to be cut. The cutting table 100 is provided with a rectangular stage for adsorbing the square workpiece 500. The cutting table 100 feeds along the X-axis direction. Optionally, the cutting tables 100 are divided into two groups, and the two groups of cutting tables 100 are arranged side by side along the Y-axis direction. The two groups of cutting tables 100 can share the image detection module 400 and the laser ranging module 300, which is conducive to saving space and reducing the cost of parts.

[0051] It should be noted that the expected cutting depth of the square workpiece 500 in the embodiment of the present invention is between 100 microns and 150 microns, and the fluctuation range of the expected cutting depth is required to be between -15 microns and +15 microns. Therefore, the cutting accuracy needs to be strictly controlled to meet the cutting requirements.

[0052] The cutting assembly 200 feeds along the Y-axis direction to cut the square workpiece 500 along the cutting path. The cutting assembly 200 in the embodiment of the present invention is a pair of cutting spindles, which can perform cutting synchronously, thereby facilitating improved cutting efficiency. In the early stage of verification, only one of the cutting spindles can be used for cutting, thereby avoiding the problem of scrapping caused by verification not meeting the accuracy requirements.

[0053] The laser distance measuring module 300 is arranged above the cutting table 100 and is used to measure the height of the square workpiece 500 by laser. The laser distance measuring module 300 determines the distance of the surface to be measured according to the time difference between the emission and the reception by emitting laser and receiving. Due to the high precision of the laser, the depth in the tiny gap (cutting path) can be measured, thereby verifying the cutting depth and avoiding the problem of product scrapping caused by finding that the requirements are not met after all the cutting is completed. It should be noted that by first measuring the height of the reference surface 110 of the cutting table 100 and then measuring the height of the surface of the square workpiece 500, the thickness of the square workpiece 500 can be reflected at intervals.

[0054] The control module is electrically connected to the laser ranging module 300, the cutting table 100 and the cutting assembly 200, and is configured to obtain the height information of a plurality of sampling points 510 on the surface of the square workpiece 500 along the cutting direction collected by the laser ranging module 300 (the distribution of the sampling points 510 is as follows Figure 4 ), and the workpiece fitting surface information is obtained according to the height information of the plurality of sampling points 510 (as shown in Figure 5), and after obtaining the workpiece fitting surface information, the cutting depth can be compensated based on the workpiece fitting surface information, thereby ensuring the consistency of the cutting depth at different positions. The control unit 600 also obtains the fitting height information of the verification point by taking verification points at several positions on the surface of the square workpiece 500 and performing interpolation calculation on the positions of the verification points according to the workpiece fitting surface information (as shown in FIG. Figure 6 As shown), and verify whether the difference between the fitted height information and the actual height information of the verification point is within the expected cutting depth fluctuation range, and determine whether to adjust the sampling point based on the verification result.

[0055] The sampling points 510 are located on a straight line parallel or perpendicular to the cutting direction. A straight line connecting any two adjacent sampling points 510 parallel or perpendicular to the cutting direction is used to obtain a set of straight lines as the workpiece fitting surface information. The verification point is a point (which can be a midpoint or other position point) on a straight line connecting any two sampling points 510 parallel or perpendicular to the cutting direction. The sampling points 510 can be selected in a direction parallel or perpendicular to the cutting direction, so that the cutting accuracy requirements can be met under the premise of minimizing the number of sampling points 510. Reducing the number of sampling points 510 helps to improve the sampling efficiency, and makes it easy to obtain the subsequent interpolation calculation results, and the calculation results can more accurately simulate the height of the surface where the cutting path is located.

[0056] Optionally, the interpolation calculation is specifically calculated as follows: connect any two sampling points 510 parallel or perpendicular to the cutting direction through a straight line, and use the height corresponding to the verification point on the straight line as the fitting height, so as to obtain the fitting height information of the verification point. For example: along the cutting direction parallel to the X-axis direction (not considering the Y-axis), connect two sampling points 510 to obtain a straight line, and obtain the straight line equation of the straight line according to the coordinates of the two sampling points 510, and by substituting the X-axis coordinate of the corresponding verification point, the fitting height value corresponding to the verification point can be obtained, and the fitting height information corresponding to the verification point can be obtained according to the fitting height value.

[0057] Optionally, the sampling point 510 can also perform self-verification after selection. Figure 5 Take the smallest rectangular unit (non-rectangular plane) in as an example, see Figure 8, A, B, C, and D in the figure represent four sampling points respectively. Through interpolation calculation, we can get the midpoint between AB as E, the midpoint between BC as F, the midpoint between CD as G, and the midpoint between DA as H. Then, there will be different fitting height values ​​at the intersection of the XY projection plane where the line connecting EG and the line connecting HF are located. Therefore, by verifying whether the difference in the fitting height of the same coordinate point on the line connecting EG and the line connecting HF is within the cutting fluctuation range, if the requirements are met, it means that the result of the interpolation calculation and the value of the sampling point meet the requirements. Otherwise, it means that the fitting result of the workpiece fitting surface information is inaccurate, so it is necessary to adjust the number and spacing of the sampling points to improve the fitting surface accuracy. There is no need to measure the actual height information of the corresponding verification points, thereby improving the cutting verification efficiency.

[0058] It should be noted that when cutting, assuming that EG is used as the cutting path and the line connecting E and G is used as the cutting line (inclined straight line), the height corresponding to point E and the height corresponding to point G are used as the reference for cutting. For example: if the cutting depth is 100 microns, the actual cutting path is to translate 100 microns downward along the height of the EG line as the cutting trajectory of the tool for compensatory cutting. In this way, any point on the cutting line meets the cutting accuracy requirements, that is, the cutting depth of any point on the EG line meets the cutting depth requirement of 100 microns. Optionally, according to Figure 5 The workpiece fitting surface information obtained by fitting is interpolated to obtain Figure 6 The interpolation cutting line 520 in the Y-axis direction and the interpolation cutting line 530 in the X-axis direction are as follows: Figure 7 When the interpolation cutting line is cut along the path, the actual height of the midpoint between any two adjacent sampling points 510 on the cutting line is measured by a measuring tool to obtain a true height, which can be compared and verified with the midpoint height calculated by linear interpolation. If the difference between the true height and the midpoint height calculated by linear interpolation is within the accuracy requirement range, the corresponding two sampling points are considered to be qualified sampling points.

[0059] It should be noted that the interpolation cutting line 520 in the Y-axis direction can be regarded as Figure 8 The set of straight lines formed by connecting points E and G along the Y-axis direction, and the interpolation cutting line 530 in the X-axis direction can be regarded as Figure 8 The set of straight lines formed by connecting points H and F along the X-axis direction. Figure 8 HF and EG are the lines connecting the verification points. If they are the lines connecting the actual cutting points, they are equivalent to the aforementioned cutting lines.

[0060] It should be noted that the verification point can be considered as the position corresponding to the interpolation point between the sampling points 510, so that the height of more verification points can be determined through the limited sampling points 510, which is convenient for verifying the verification points, so as to meet the cutting accuracy requirements. If the cutting depths corresponding to the verification points are all within the expected cutting depth range, it can be considered that the number and spacing of the sampling points 510 are appropriately selected, and the cutting accuracy meets the requirements. Otherwise, the cutting accuracy requirements are not met, and more sampling points 510 need to be selected to fit the workpiece fitting surface information that is closer to the actual situation. The more sampling point 510 data of the workpiece fitting surface information, the closer it is to the actual surface, but the more sampling point 510 data, the lower the fitting efficiency, which in turn affects the cutting efficiency. Therefore, it is necessary to take into account the cutting accuracy while ensuring the cutting efficiency.

[0061] Optionally, the verification point is the midpoint between any two straight lines connecting the sampling points 510 parallel or perpendicular to the cutting direction. This allows the accuracy of the fitting result to be quickly verified and makes it easier to fit the workpiece fitting surface information that is closer to the actual situation, especially more accurately fitting the height of the surface where the cutting path is located, thereby improving the cutting accuracy.

[0062] The square workpiece cutting system based on laser height measurement provided by the embodiment of the present invention can accurately restore the fitting surface information of the workpiece by measuring the height of the specified position of the workpiece, thereby compensating for the height of the cutting components at different positions, and interpolating and calculating the height of any position point based on the fitting surface information. In this way, the height of some position points on the cutting path can be verified to ensure the cutting accuracy, and the cutting is adjusted in real time according to the surface height to ensure the consistency of the cutting depth, and the generation of cutting waste can be minimized, thereby saving costs. Moreover, after the verification meets the requirements, there is no need to continue verification, and subsequent direct cutting can be achieved, which is beneficial to improving cutting efficiency.

[0063] In some embodiments, there are two ways to measure the height of multiple sampling points 510. One is fixed-point height measurement, that is, only a part of the measurement points are selected as sampling points 510 according to experience. The other is to continuously collect the heights of multiple points along the cutting direction by scanning. Since the height data of so many points are not needed when fitting the surface information of the workpiece, some points can be randomly selected as sampling points 510, and the fitting can be verified by the heights of the points measured between the sampling points 510.

[0064] The following is a detailed description of the first fixed-point height measurement method:

[0065] like Figure 4 and Figure 5As shown, the heights of the multiple sampling points 510 are obtained by fixed-point measurement, and the multiple sampling points 510 are arranged along the X-axis direction and equally divided in the Y-axis direction. The aspect ratio of the minimum rectangular unit (not necessarily a rectangular plane) formed by the lines connecting the sampling points 510 along the X-axis direction and the lines connecting the sampling points 510 along the Y-axis direction is close to the aspect ratio of the square workpiece 500, which is more conducive to evenly dividing the minimum rectangular unit, and the distribution of the sampling points 510 is more uniform, and the obtained workpiece fitting surface information is more accurate. Optionally, more sampling points are selected in the Y-axis direction, so that the sampling points are denser, for example, the minimum rectangular unit is close to a square, which is conducive to improving the fitting accuracy.

[0066] Optionally, verifying whether the difference between the fitted height information and the actual height information of the verification point is within the expected cutting depth fluctuation range also includes two methods, one of which specifically includes:

[0067] After all cutting is completed along the cutting path, the cutting depth corresponding to the midpoint of two adjacent N sampling points 510 is verified; if the difference between the real height information of the N verification points on the square workpiece 500 and the corresponding real height information is all within the expected cutting depth fluctuation range, it indicates that the cutting accuracy of the square workpiece 500 meets the requirements. If the difference between the fitting height information of the N verification points on the square workpiece and the corresponding real height information exceeds the expected cutting depth fluctuation range, the cutting is stopped and the number of sampling points is increased again and verified again N times until the N verifications meet the accuracy requirements.

[0068] If M consecutive square workpieces 500 in a batch of incoming materials are all verified, it means that the cutting accuracy of the batch of incoming materials meets the requirements, and the subsequent square workpieces 500 are directly cut. The real height information of the verification point is obtained in advance by the laser ranging module or obtained by other measurement tools after cutting.

[0069] For example: N is 20, M is 10, that is, 20 verification points are taken on each square workpiece 500 to verify whether the cutting depth meets the accuracy requirement, and 10 workpieces in the same batch of workpieces are verified continuously. If all meet the cutting accuracy requirement, it is considered that the selection of sampling points 510 meets the requirement, and the remaining workpieces of the batch can be directly cut without verification; if one of the workpieces fails to be verified, it is necessary to adjust the number and spacing of the sampling points 510, re-fit and verify until the requirements are met.

[0070] Optionally, in order to reduce the generation of cutting waste, the embodiment of the present invention further provides a verification method for fitting the sampling point 510 obtained by measuring the height at a fixed point, specifically:

[0071] The fitting height information corresponding to the verification point between two adjacent sampling points 510 is verified for the first time. If the difference between the real height information and the fitting height information corresponding to the verification point is within the expected cutting depth fluctuation range, the verification is repeated N-1 times in the same manner. If it is found that the difference between the real height information and the fitting height information corresponding to any verification point exceeds the expected cutting depth fluctuation range, the cutting is stopped and the number of sampling points 510 is increased again to verify again N times. After N verifications meet the accuracy requirements, it is indicated that the cutting accuracy of the square workpiece 500 meets the requirements.

[0072] If M consecutive square workpieces 500 in a batch of incoming materials are all verified, it means that the cutting accuracy of the batch of incoming materials meets the requirements, and the subsequent square workpieces 500 can be cut directly. The real height information of the verification point can be obtained in advance through the laser ranging module, that is, the laser ranging module first takes multiple sampling points 510, a part of which is fitted to obtain fitting surface information, and the remaining part is used as verification points to verify the subsequent fitting height information.

[0073] Exemplarily, N in the embodiment of the present invention can be 20, that is, after a total of 20 verifications, it can be considered that the workpiece fitting surface information corresponding to the number of sampling points 510 taken previously and the distance between adjacent sampling points 510 meets the requirements of cutting accuracy. On the contrary, as long as the cutting accuracy requirements are not met at a certain time, the cutting is stopped immediately and the number of sampling points 510 needs to be increased again to obtain the workpiece fitting surface information that is closer to the actual surface condition, and the verification is restarted N times, which is conducive to improving the cutting accuracy. M is 10, that is, 10 workpieces in the same batch of workpiece materials are continuously verified. If all of them meet the cutting accuracy requirements, it is considered that the selection of sampling points 510 meets the requirements, and the remaining workpieces of the batch of materials can be directly cut without verification; if one of the workpieces fails to be verified, it is necessary to adjust the number and spacing of the sampling points 510, re-fit and verify until the requirements are met.

[0074] Optionally, after the cutting is completed, the actual height information of the verification point may be measured by a more accurate measuring tool to determine the accuracy of the above verification result.

[0075] The second scanning height measurement method is described in detail below:

[0076] Optionally, the actual height information of the multiple sampling points 510 is obtained by scanning measurement, and the height value of the midpoint (verification point) between two adjacent sampling points 510 is collected at the same time, and the fitting accuracy of the workpiece fitting surface information is verified by the actual height information of the verification point between two adjacent sampling points 510.

[0077] Specifically, if the difference between the actual height of the verification point sampling point 510 and the height of the corresponding position of the fitting surface information exceeds the preset threshold (expected cutting depth fluctuation range), it is necessary to re-determine the number of sampling points 510 and the distance between two adjacent sampling points 510. If it does not exceed the preset threshold, it is considered that the cutting accuracy requirement is met, and cutting can be continued in the current manner.

[0078] In some embodiments, the laser ranging module 300 is connected to the cutting assembly 200 via a connecting piece and moves synchronously with the cutting assembly 200, that is, the laser ranging module 300 moves synchronously with the cutting assembly 200, so that the depth of the cutting path can be verified while cutting, which is beneficial to improving cutting efficiency.

[0079] Optionally, the laser ranging module 300 is connected to a Y-axis driving module installed on the top of the base, and the Y-axis driving module drives the laser ranging module 300 to move along the Y-axis direction, thereby realizing switching between different cutting action tables. In this way, the height of the square workpiece 500 on the two cutting workbenches 100 can be measured by one laser ranging module 300 in a time-sharing manner, which is beneficial to saving space and cost of the entire device.

[0080] In some embodiments, continue to refer to Figure 1 The square workpiece cutting system based on laser height measurement also includes: an image detection module 400, which is connected to the Y-axis drive module installed on the top of the base, and is used to obtain the surface image information of the square workpiece 500. The control unit 600 is electrically connected to the image detection module 400, and is used to automatically align the square workpiece 500 or check the cutting condition when measuring the height. For example, the cutting condition check includes whether the cutting knife mark is located in the middle of the cutting path, whether there is a knife mark offset, whether the knife mark width meets the requirements, and whether the knife mark is broken. Optionally, a positioning mark is set on the edge of the square workpiece 500, and the positioning mark is quickly identified by the image detection module 400 for alignment, thereby improving the positioning efficiency and accuracy. In addition, the image detection module 400 can also verify the cutting trajectory to avoid deviation of the cutting path and cause product scrapping.

[0081] Based on the same inventive concept, Fig.10 As shown, an embodiment of the present invention further provides a square workpiece cutting method based on laser height measurement, based on the square workpiece cutting system described in the first aspect (the specific content of the cutting system is not repeated here), the square workpiece cutting method comprises the following steps:

[0082] S100, obtaining the reference plane height of the cutting workbench 100.

[0083] Specifically, the height of the cutting table 100 is first measured. The height measuring tool may be a laser distance measuring module 300, which has high measurement accuracy and can detect the depth of the cutting path.

[0084] S200 , obtaining heights of a plurality of sampling points 510 on the surface of a square workpiece 500 placed on a cutting table 100 along a cutting direction.

[0085] Specifically, the sampling points 510 are selected along the cutting direction (X-axis direction and Y-axis direction), so that the distribution of the sampling points 510 is more uniform, which is beneficial to improving the accuracy of the workpiece fitting surface information.

[0086] S300 , obtaining workpiece fitting surface information according to the height fitting of the plurality of sampling points 510 .

[0087] Specifically, a plurality of sampling points 510 located along the X-axis direction and having the same Y-axis coordinate are sequentially connected to form a broken line, and a plurality of sampling points 510 located along the Y-axis direction and having the same X-axis coordinate are sequentially connected to form a broken line. The workpiece fitting surface information can be fitted through a plurality of such broken lines, that is, the surface condition of the entire square workpiece 500 is indirectly fitted through the heights of a limited number of sampling points 510, which is conducive to reflecting the heights of different positions, so as to compensate the depth of the cutting tool (that is, the height of the cutting component 200) according to the surfaces at different heights to ensure the consistency of the cutting depth.

[0088] S400, taking verification points at a plurality of positions on the surface of the square workpiece, and performing interpolation calculation on the positions of the verification points according to the workpiece fitting surface information to obtain fitting height information at the verification points.

[0089] Specifically, the interpolation calculation can obtain the heights of more verification points (which may be on the line connecting the sampling points 510 or not). In addition, the sampling points 510 may be located on the cutting path or not when selected, and the height of the verification point located on the cutting path is calculated by interpolation, so that the real height of the verification point can be verified after cutting along the cutting path. Optionally, the verification point can also be the midpoint between two adjacent sampling points 510, which is conducive to improving the verification accuracy.

[0090] S500, verifying whether the difference between the actual height information and the fitted height information of the verification point is within the expected cutting depth fluctuation range, and determining whether to adjust the sampling point according to the verification result.

[0091] Specifically, by comparing the difference between the actual height information of the verification point and the fitting height information, it is determined whether the cutting accuracy requirement is met. If the difference between the actual height information of the verification point and the fitting height information is within the expected cutting depth fluctuation range, it is considered that the cutting accuracy requirement is met. Otherwise, it is considered that the cutting accuracy requirement is not met, and the number and spacing of the sampling points 510 need to be adjusted (increasing the number of sampling points 510 and reducing the spacing), so that the fitting surface information is closer to the actual situation to improve the fitting accuracy, and the above steps are repeated until the cutting accuracy requirement is met.

[0092] The square workpiece cutting method based on laser height measurement provided in the embodiment of the present invention can accurately restore the fitting surface information of the workpiece by measuring the height of the specified position of the workpiece, and calculate the height of any position point by interpolation based on the fitting surface information. In this way, the height of some position points on the cutting path can be verified, thereby ensuring the cutting accuracy, and the cutting is adjusted in real time according to the surface height to ensure the consistency of the cutting depth, and the generation of cutting waste can be minimized, thereby saving costs. Moreover, after the verification meets the requirements, there is no need to continue verification, and subsequent direct cutting can be achieved, which is beneficial to improving cutting efficiency.

[0093] Those skilled in the art will appreciate that the various operations, methods, steps, measures, and schemes discussed in the present invention may be alternated, modified, combined, or deleted. Further, other steps, measures, and schemes in the various operations, methods, and schemes discussed in the present invention may also be alternated, modified, rearranged, decomposed, combined, or deleted. Further, the steps, measures, and schemes in the prior art that are similar to those disclosed in the present invention may also be alternated, modified, rearranged, decomposed, combined, or deleted.

[0094] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0095] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0096] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific conditions.

[0097] In the description of this specification, specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. It should be understood that although the steps in the flowchart of the accompanying drawings are displayed in sequence as indicated by the arrows, these steps are not necessarily performed in sequence in the order indicated by the arrows. Unless clearly stated herein, there is no strict order restriction on the execution of these steps, and they may be performed in other orders. Moreover, at least a portion of the steps in the flowchart of the accompanying drawings may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily performed at the same time, but may be performed at different times, and their execution order is not necessarily performed in sequence, but may be performed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A square workpiece cutting system based on laser height measurement, used for half-cutting the square workpiece, characterized in that: include: At least one set of cutting workbenches, the cutting workbenches are used to place square workpieces to be cut, the cutting workbenches are provided with a rectangular stage for adsorbing the square workpieces, and the cutting workbenches move in a feeding manner along the X-axis direction; A cutting assembly, wherein the cutting assembly moves along the Y-axis direction to cut the square workpiece; A laser distance measuring module, which is arranged above the cutting workbench and is used for laser height measurement of the square workpiece; A control module, the control module is electrically connected to the laser ranging module, the cutting table and the cutting assembly, and is configured to obtain the height information of multiple sampling points on the surface of the square workpiece along the cutting direction collected by the laser ranging module, and obtain the workpiece fitting surface information by fitting the height information of the multiple sampling points; take verification points at several positions on the surface of the square workpiece, and perform interpolation calculation on the positions of the verification points according to the workpiece fitting surface information to obtain the fitting height information of the verification points; verify whether the difference between the fitting height information and the actual height information of the verification points is within the expected cutting depth fluctuation range, and determine whether to adjust the sampling points according to the verification results; wherein the sampling points are located on a straight line parallel or perpendicular to the cutting direction, and a straight line connecting any two adjacent sampling points parallel or perpendicular to the cutting direction is connected to obtain a set of straight lines as the workpiece fitting surface information, and the verification point is a point on a straight line connecting any two sampling points parallel or perpendicular to the cutting direction; Verification points are taken at several positions on the surface of the square workpiece, and interpolation calculation is performed on the positions of the verification points according to the fitting surface information of the workpiece to obtain fitting height information of the verification points, including: Determine a straight line formed by connecting any two adjacent sampling points parallel or perpendicular to the cutting direction, and use the height corresponding to the verification point on the straight line as the fitting height value, so as to obtain the fitting height information of the verification point; wherein the verification point is located at the midpoint of two adjacent sampling points along the X-axis direction and the midpoint of two adjacent sampling points along the Y-axis direction; And, verifying whether the difference between the fitted height information and the actual height information of the verification point is within the expected cutting depth fluctuation range, and determining whether to adjust the sampling point according to the verification result, including: Get the coordinates of the four sampling points at the vertices of the minimum rectangular unit; Obtain four verification points corresponding to the four sampling points of the minimum rectangular unit by interpolation calculation, and respectively obtain the connecting lines of two verification points corresponding to the minimum rectangular unit; The fitting height values ​​corresponding to the intersection of the two lines on the XY projection plane are obtained respectively, and the result of the interpolation calculation and the rationality of the sampling point value are determined according to whether the difference of the fitting height is within the cutting fluctuation range.

2. The square workpiece cutting system based on laser height measurement according to claim 1, characterized in that: The heights of the plurality of sampling points are obtained by fixed-point measurement, and the plurality of sampling points are arranged along the X-axis direction and are equally divided along the Y-axis direction.

3. The square workpiece cutting system based on laser height measurement according to claim 2, characterized in that: Verify whether the difference between the fitted height information and the actual height information of the verification point is within the expected cutting depth fluctuation range, including: After all cutting is completed along the cutting path, the real height information corresponding to the N verification points is verified; if the difference between the fitting height information of the N verification points on the square workpiece and the corresponding real height information is all within the expected cutting depth fluctuation range, it indicates that the cutting accuracy of the square workpiece meets the requirements; if the difference between the fitting height information of the N verification points on the square workpiece and the corresponding real height information exceeds the expected cutting depth fluctuation range, the cutting is stopped and the number of sampling points is increased again and verified again N times until the N verifications meet the accuracy requirements; If M consecutive square workpieces in a batch of incoming materials are verified, it means that the cutting accuracy of the batch of incoming materials meets the requirements and the subsequent square workpieces can be cut directly; wherein, the real height information of the verification point is obtained in advance through the laser ranging module or obtained through other measuring tools after cutting.

4. The square workpiece cutting system based on laser height measurement according to claim 2, characterized in that: Verify whether the difference between the fitted height information and the actual height information of the verification point is within the expected cutting depth fluctuation range, including: The fitting height information of the verification point between two adjacent sampling points is verified for the first time. If the difference between the real height information and the fitting height information corresponding to the verification point is within the expected cutting depth fluctuation range, the verification is repeated N-1 times in the same manner. If it is found that the difference between the real height information and the fitting height information corresponding to any verification point exceeds the expected cutting depth fluctuation range, the cutting is stopped and the number of sampling points is increased again and verified again N times until the N verifications meet the accuracy requirements. If M consecutive square workpieces in a batch of incoming materials are verified, it means that the cutting accuracy of the batch of incoming materials meets the requirements, and the subsequent square workpieces are directly cut. The real height information of the verification point is obtained in advance by the laser ranging module.

5. The square workpiece cutting system based on laser height measurement according to claim 1, characterized in that: Verify whether the difference between the fitted height information and the actual height information of the verification point is within the expected cutting depth fluctuation range, including: The heights of the plurality of sampling points are obtained by scanning and measuring by the laser ranging module, and the actual height information of the verification point is obtained by scanning at the same time, and the verification is performed by comparing the actual height information of the verification point with the fitting height information of the verification point; If the difference between the actual height information of the verification point and the fitting height information at the corresponding position of the fitting surface information exceeds the expected cutting depth fluctuation range, it is necessary to redetermine the number of sampling points and the distance between two adjacent sampling points.

6. The square workpiece cutting system based on laser height measurement according to claim 1, characterized in that: The laser distance measuring module is connected to the cutting assembly through a connecting piece and moves synchronously with the cutting assembly; or, the laser distance measuring module is connected to a Y-axis driving module installed on the top of the base.

7. The square workpiece cutting system based on laser height measurement according to claim 6, characterized in that: Also includes: An image detection module is connected to a Y-axis driving module installed on the top of the base and is used for automatically aligning or checking the cutting condition of a square workpiece.

8. The square workpiece cutting system based on laser height measurement according to claim 7, characterized in that: The cutting workbenches are divided into two groups, and the two groups of cutting workbenches are arranged side by side along the Y-axis direction and share the image detection module and the laser ranging module.

9. The square workpiece cutting system based on laser height measurement according to any one of claims 1 to 8, characterized in that: The expected cutting depth of the square workpiece is between 100 microns and 150 microns, and the fluctuation range of the expected cutting depth is required to be between -15 microns and +15 microns.

10. A square workpiece cutting method based on laser height measurement, based on the square workpiece cutting system based on laser height measurement as claimed in any one of claims 1 to 9, characterized in that: The cutting method of the square workpiece comprises: S100, obtaining the reference plane height of the cutting table; S200, obtaining the heights of a plurality of sampling points on the surface of a square workpiece placed on the cutting workbench along a cutting direction; S300, obtaining workpiece fitting surface information according to the height fitting of the plurality of sampling points; S400, taking verification points at a plurality of positions on the surface of the square workpiece, and performing interpolation calculation on the positions of the verification points according to the workpiece fitting surface information to obtain fitting height information of the verification points; S500, verifying whether the difference between the actual height information and the fitted height information of the verification point is within the expected cutting depth fluctuation range, and determining whether to adjust the sampling point according to the verification result.

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